Hydraulic pump and motor module for use in a vehicle

ABSTRACT

A module for use in connection with a dual pump apparatus, where each pump is hydraulically connected to a separate hydraulic motor. The module may include motors and/or an engine for ease of installation in a vehicle, providing flexibility for different applications. Various brackets, stabilizers and other elements are provided to assist in securing the module to the vehicle.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 11/380,111 filed Apr. 25, 2006, which is a continuation of U.S.patent application Ser. No. 10/767,315, filed on Jan. 28, 2004, now U.S.Pat. No. 7,056,101, which is a continuation-in-part of application Ser.No. 10/175,206, filed Jun. 19, 2002, now U.S. Pat. No. 6,705,840. Thisapplication also claims priority from U.S. Provisional PatentApplication No. 60/693,570 filed on Jun. 24, 2005 and U.S. ProvisionalPatent Application No. 60/698,699, filed on Jul. 13, 2005. All of theseprior applications and patents are incorporated by reference in theirentirety.

BACKGROUND OF THE INVENTION

This invention relates to hydraulic pumps. This invention also relatesto hydraulic pumps and wheel motors used in connection with vehicles,and to modules incorporating such pumps, motors and other components forassembly in a vehicle.

SUMMARY OF THE INVENTION

A dual tandem pump having an input shaft that is separate from the pumpinput shafts is disclosed herein. Also disclosed herein are dual pumpand wheel motor modules for use in connection with a vehicle. Variousembodiments are depicted to provide easy mounting of the pump and motormodule to the frame or other components of the vehicle. In certainembodiments, the vehicle engine is provided as part of the module forsimplicity in assembly.

The details of this invention are set forth below in connection with thedetailed description of the embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an external side view of a tandem pump in accordance with oneembodiment of this invention.

FIG. 2 is a cross-sectional view along the lines 2-2 in FIG. 1.

FIG. 3 is a cross-sectional side view along the lines 3-3 in FIG. 2.

FIG. 4 is a schematic of the hydraulic circuit of the embodiment of thisinvention shown in FIG. 1.

FIG. 5 is a cross-sectional side view of a second embodiment of thisinvention.

FIG. 6 is a schematic of the hydraulic circuit of the embodiment of thisinvention shown in FIG. 5.

FIG. 7 is a cross-sectional side view of a third embodiment of thisinvention.

FIG. 8 is a schematic of the hydraulic circuit of the embodiment of thisinvention shown in FIG. 7.

FIG. 9 is a side view of a fourth embodiment of this invention.

FIG. 10 is a cross-sectional side view of a fifth embodiment of thisinvention.

FIG. 11 is a cross-sectional view of the fifth embodiment of the pumpapparatus shown along the lines 11-11 in FIG. 10.

FIG. 12 is a cross-sectional view of an end cap of the fifth embodimentof this invention shown along the lines 12-12 in FIG. 10.

FIG. 13 is a schematic showing the embodiment of FIGS. 10-12.

FIG. 14 is a cross-sectional side view of a sixth embodiment of thepresent invention.

FIG. 15 is a top plan view of a further embodiment of this invention.

FIG. 16 is a top plan view of yet a further embodiment of thisinvention.

FIG. 17 is a side elevational view of a vehicle in accordance with afurther embodiment of this invention, having a bracket-mounted dual pumpmodule with an engine attached.

FIG. 18 is a front, partially sectioned elevational view of theinstalled bracket-mounted dual pump module shown in FIG. 17, along thelines 18-18.

FIG. 19 is a side elevational view of the dual pump module shown in FIG.17.

FIG. 20 is a front elevational view of the dual pump module shown inFIG. 17.

FIG. 21 is a plan view with a partial cutaway of the bracket-mounteddual pump module shown in FIG. 19 with the prime mover removed.

FIG. 22 is a side elevational view of a portion of the dual pump moduleshown in FIG. 19.

FIG. 23 is a side elevational view of one of the bracket componentsshown in FIG. 19.

FIG. 24 is a side elevational view of one of the bracket componentsshown in FIG. 19.

FIG. 25 is a partial schematic view of an arrangement of a dual pumpmodule in accordance with an embodiment of this invention for use in avehicle.

FIG. 26 is a side elevational view of a vehicle in accordance withanother embodiment of this invention.

FIG. 27 is a front elevational view of the dual pump module shown inFIG. 26.

FIG. 28 is a front, partially sectioned elevational view of theinstalled dual pump module shown in FIG. 26, along the lines 28-28.

FIG. 29 is a side elevational view of the dual pump module shown in FIG.26.

FIG. 30 is a side elevational view of the basic dual pump module shownin FIG. 29 without an engine attached and with a portion of one of thebrackets removed for clarity.

FIG. 31 is a side elevational view of a vehicle having a bracket-mounteddual pump module with an engine in accordance with a further embodimentof this invention.

FIG. 32 is a front, partially sectioned elevational view of theinstalled bracket-mounted dual pump module shown in FIG. 31, along thelines 32-32.

FIG. 33 is a side elevational view of the dual pump module shown in FIG.31.

FIG. 34 is a front elevational view of the dual pump module shown inFIG. 31.

FIG. 35 is a side elevational view of a vehicle in accordance withanother embodiment of this invention, including a dual pump modulewithout an engine attached.

FIG. 36 is a front, partially sectioned elevational view of theinstalled dual pump module shown in FIG. 35, along the lines 36-36.

FIG. 37 is a side elevational view of the dual pump module shown in FIG.35.

FIG. 38 is a side elevational view of a vehicle in accordance withanother embodiment, including a dual pump module with an engineattached.

FIG. 39 is a rear, partially sectioned elevational view of the installedbracket-mounted dual pump module shown in FIG. 38, along the lines39-39.

FIG. 40 is a side elevational view of the bracket-mounted dual pumpmodule shown in FIG. 38.

FIG. 41 is a side elevational view of a vehicle in accordance withanother embodiment, including a dual pump module which may be installedwith or without an engine attached.

FIG. 42 is a rear elevational view of the installed bell housing dualpump module shown in FIG. 41.

FIG. 43 is a rear elevational view of a bracket-mounted dual pump moduleinstalled in a vehicle frame such as that shown in FIG. 41.

FIG. 44 is a side elevational view of a vehicle in accordance withanother embodiment, including a dual pump module with an engine, wherethe module is mounted to the inside of the frame rails.

FIG. 45 is a rear elevational view of the installed bell housing dualpump module shown in FIG. 44.

FIG. 46 is a rear elevational view of a further embodiment similar toFIG. 45, but incorporating a crossbeam approach and depicting aninstalled bracket-mounted dual pump module in a structuralconfiguration.

FIG. 47 is a rear elevational view of an embodiment similar to FIG. 46,but incorporating rectangular or square tubes instead of U-brackets anddepicting a bell housing dual pump module.

FIG. 48 is a rear elevational view of an embodiment similar to FIG. 47,but incorporating rectangular or square tubes with tube walls in avertical orientation.

FIG. 49 is a rear elevational view of an installed dual pump module inaccordance with another embodiment similar to FIG. 48, but incorporatingcastings in a structural crossbeam configuration.

FIG. 50 is an elevational view of the inner end of the casting used inFIG. 49 to connect the pump assembly to each wheel motor.

FIG. 51 is either a front or rear elevational view of the casting shownin FIG. 50.

FIG. 52 is an elevational view of the outer end of the casting shown inFIG. 50.

FIG. 53 is a side elevational view of a vehicle in accordance withanother embodiment, including a dual pump module installed in a vehiclewith a straight frame.

FIG. 54 is a partially sectioned view of the basic dual pump module withthe hydraulic power take off assembly shown in FIG. 56.

FIG. 55 is a side elevational view of the dual pump module shown in FIG.53.

FIG. 56 is a plan view of the dual pump module shown in FIG. 53.

FIG. 57 is a front, partially sectioned elevational view of the vehicleshown in FIG. 53, along the lines 57-57.

FIG. 58 is a top plan view of the straight frame dual pump module shownin FIG. 53.

FIG. 59 is a side elevational view of a vehicle having a dual pumpmodule installed in a vehicle with an offset bend in the frame.

FIG. 60 is a front, partially sectioned elevational view of the vehicleshown in FIG. 59, along the lines 60-60.

DETAILED DESCRIPTION OF THE DRAWINGS

FIGS. 1-16 are directed to a dual pump apparatus and depict differentembodiments thereof. FIGS. 17 to 60 are directed to various modulesincorporating, among other things, a dual pump apparatus.

One embodiment of this invention is shown in FIGS. 1, 2, 3 and 4, whichdepict a pump apparatus 10 having a unitary housing 12. In theembodiment described below, two generally identical pumps 11 a and 11 bare disclosed within unitary housing 12, and identical numerals with theletters a and b are used to reference identical parts. It will beunderstood by one of skill in the art that pumps 11 a and 11 b need notbe identical and that substantial variations are possible to one or theother within the scope of this invention. Pumps 11 a and 11 b are shownas the rotating axial piston type, although other designs could be usedwith minor modifications within the scope of this invention. Forconvenience, only certain elements of pump 11 a and its relatedstructure are described in detail herein. It will be understood that thecorresponding structure of pump 11 b is identical in the embodimentsdepicted and need not be similarly described.

Housing 12 forms two generally identical pump chambers or cavities 29 aand 29 b and a gear chamber or cavity 30 formed therebetween, thusproviding an integral housing for pumps 11 a and 11 b. A pair of endcaps 16 a and 16 b are mounted on opposite ends of housing 12 and act toseal pump chambers 29 a and 29 b, and may be secured thereto by screws22 or another means. A cover 23 is secured to the bottom of housing 12to close gear chamber 30.

With regard to pump 11 a on the left hand side of FIGS. 1, 2 and 3, itcan be seen that a pump cylinder block 31 a comprising a plurality ofaxial pistons 38 a is mounted on running plate 37 a, which may be usedfor additional strength and durability. Cylinder block 31 a could alsorun directly on a surface formed on end cap 16 a. The porting in endcaps 16 a and 16 b can be of the design shown in e.g., U.S. Pat. No.6,332,393, the terms of which are incorporated by reference.

End cap 16 a includes hydraulic porting 26 a for the hydraulic fluid.System ports 41 a and 42 a are formed on the external surface thereof.In the view shown in FIG. 1, plugs 43 are used to seal system ports 41a, 41 b, 42 a and 42 b for shipping; in use the system ports would beconnected to hoses or the like. As shown in the schematic depicted inFIG. 4, ports 41 a and 42 a are connected to motor 40 a while ports 41 band 42 b are connected to motor 40 b. Motors 40 a and 40 b could bewheel motors in a typical zero turn vehicle design; they could also bereplaced with other hydraulic devices in other applications. A bypass 66a and 66 b is provided for each pump 11 a and 11 b to permit, e.g.,movement of the vehicle when it is not under power.

Pump 11 a is of the cradle mounted swash plate design; as shown in FIG.3, swash plate 32 a is mounted in pump chamber 29 a on cradle bearings46 a mounted on the inner wall of housing 12. Pistons 38 a run againstswash bearing 33 a mounted in swash plate 32 a. Trunnion arm 21 a isengaged to a control block 45 a that is engaged to swash plate 32 a, sothat rotation of trunnion arm 21 a causes movement of swash plate 32 ato the various stroked forward or reverse positions, or to the neutralposition.

As shown in FIG. 4, an external reservoir 68 is used for storinghydraulic fluid. The hydraulic fluid is pulled from reservoir 68 throughfilter 65 into charge inlets 47 a and 47 b, and hence to charge pumps 18a and 18 b, respectively. Charged fluid is driven into charge gallery 49a and then to the porting in end cap 16 a, and a charge relief 75 a isprovided to keep pressures within the normal operating range. Since inthis embodiment pump chambers 29 a and 29 b are sealed from one another,a plurality of case drains 69 a and 69 b are provided to remove oil frompump chambers 29 a and 29 b, respectively. The separate case drains 69 aand 69 b may be located in a variety of locations, such as end caps 16 aand 16 b. Check valves 67 a and 67 b are used to maintain the properhydraulic flow within end caps 16 a and 16 b. A pair of charge pressurerelief valves 75 a and 75 b is connected to the porting for charge pumps18 a and 18 b, respectively.

Input shaft 14 extends into housing 12; it can be driven by a primemover such as engine 121 shown in FIG. 17 through a pulley, such aspulley 51 shown in FIG. 4, or some other means. Bevel gear 36 is mountedon input shaft 14 inside gear chamber 30 and is drivingly engaged to asecond bevel gear 35 mounted on first pump shaft 27. Pump shaft 27extends from gear chamber 30 into first pump chamber 29 a and is engagedto and drivingly rotates pump cylinder block 31 a. Bearing 44 a providessupport within housing 12. Pump shaft 27 is joined to and drives shaft28 through coupler 34, which may be of a known design using a powderedmetal part with splines to interlock shafts 27 and 28, or a cut steelpart with a broached inner diameter to form the interlock, or a similardesign. Pump shaft 28 also extends from gear chamber 30 into pumpchamber 29 b where it engages and drivingly rotates pump cylinder block31 b in a similar manner. As shown in, e.g., FIG. 3, input shaft 14 isgenerally perpendicular to pump shafts 27 and 28 and extends out theside of housing 12 as opposed to the ends thereof, which provides theuser with flexibility in the application.

As shown in, e.g., FIG. 3, input shaft 27 extends through end cap 16 ainto charge housing 20 a to drive charge pump 18 a, which can be agerotor style such as is shown or some other style of charge pump, suchas a vane pump, geroller, gear pump or any other known design. End cap16 a may be secured to housing 12 by means of screws 24 or the like. Thelocation of input shaft 14 on the side of housing 12 permits thelocation of charge pumps 18 a and 18 b on opposite ends of housing 12.Specifically, charge pump 18 a is located within charge pump housing 20a mounted on end cap 16 a. A similar charge pump 18 b may be mounted ina similar manner in charge pump housing 20 b on the other end ofapparatus 10. It is possible that only one of the charge pumps would berequired, depending on the application for which the pump apparatus 10is to be used. Similarly, the output of one charge pump mounted on oneend cap could be attached by means of internal or external hoses orintegral passages to provide charge pressure to the other pumpassociated with the other end cap.

It will also be understood that these embodiments could includeadditional gear reduction. For example, in FIG. 3, a gear reductioncould be used between bevel gear 36 on input shaft 14 and bevel gear 35on pump shaft 27. Furthermore, it will be understood that bevel gears 35and 36 could be replaced with another means for creating a right angleturn of the rotational force, such as helical gears, a worm gear drivinga spur gear and the like.

FIG. 5 shows a second embodiment of this invention, where like numeralsindicate identical structure with previous figures. A pump apparatus 50has a housing 52 which creates a gear chamber 56 and a first pumpchamber 59 a and a second pump chamber 59 b. A case fluid passage 55 ais formed in housing 52 to connect pump chamber 59 a and gear chamber56, and case fluid passage 55 b similarly connects pump chamber 59 bwith gear chamber 56, both to permit hydraulic oil to flow between thepump chambers 59 a and 59 b and the gear chamber 56. Since both pumpchambers 59 a and 59 b and gear chamber 56 are hydraulically connectedin this embodiment, a single case drain 69 to permit oil to flow toreservoir 68 can be formed anywhere in housing 52; if it is in the gearchamber 56, as shown in FIG. 6, it will assist in preventingcontamination of pumps 11 a and 11 b with debris from bevel gears 36, 35a and 35 b and assist in reduction of heat, as the warmer fluid frompumps 11 a and 11 b will be carried to the center of housing 52. Itcould, however, be formed elsewhere in the circuit depending on theapplication requirements. The use of a single case drain also reducesmachining requirements and the number of fittings required.

In this second embodiment, input shaft 54 is driven by input pulley 51and extends through housing 52, and through cover 53, which includesbearing 57 therein to support shaft 54. Output pulley 58 may be attachedto the end of shaft 54 to drive an auxiliary device such as a mower deckor other device. Cover 53 is strengthened to support bearing 57 used torotatably support shaft 54 and the torque loads from output pulley 58.

It will be noted that using through shaft 54 as the input shaftprecludes the use of a coupler to drive pump input shafts 63 a and 63 b.An alternative means of driving these shafts is shown in FIG. 5 whereinput shaft 54 has a first bevel gear 36 mounted thereon and drivinglyengaged to a first driven bevel gear 35 a mounted on and driving firstpump shaft 63 a and a second driven bevel gear 35 b which is similarlymounted on and driving second pump shaft 63 b. Such an alternativearrangement could also be used with the first embodiment in place ofcoupler 34. A further benefit of this design is that pump shafts 63 aand 63 b can be sized appropriately for pumps 11 a and 11 b; only inputshaft 54 needs to be sized appropriately to handle the torque of bothpumps 11 a and 11 b as well as the torque requirements of an auxiliarydevice attached to output pulley 58.

A third embodiment of this invention is shown in FIG. 7, which issimilar in many ways to the embodiment as shown in FIG. 5. Pumpapparatus 70 includes a housing 72 with cover 73 secured thereto. Inputshaft 74 extends through housing 72 and cover 73, where it is supportedby bearing 77, to extend out of gear chamber 56 to drive auxiliary pump78 through coupler 76, which also may be of the internal splinestructure or other known structure. Auxiliary pump 78 couldalternatively be driven directly by input shaft 74, thus eliminating theneed for coupler 76. Optional hardened washers 25 may be mountedadjacent to gears 35 a, 35 b and 36 to provide support for such gearsrunning against housing 72.

Auxiliary pump 78 is mounted in auxiliary pump housing 79 mounted oncover 73, and it can be used for driving external devices such as a decklift or the like. The auxiliary out and auxiliary return are depictedschematically in FIG. 8. As with the embodiment depicted in FIG. 6, thisembodiment requires only a single case drain 69 to reservoir 68.

Yet another embodiment is depicted in FIG. 9, which is structurallysubstantially identical to the embodiment shown in FIG. 1. FIG. 9 showsa pump apparatus 80, where the key differences with FIG. 1 are that pumpshafts 87 and 88 extend out of charge pump housings 82 a and 82 b,respectively, and input shaft 84 extends out of cover 83. A plurality ofcooling fans 81 a and 82 b are mounted on pump shafts 87 and 88respectively, while fan 81 c may be mounted on input shaft 84. It isunlikely, though possible, that all three fans 81 a-c would be neededfor a single application.

One or more of fans 81 a-c may be used depending on the applicationneeds and if 81 a and 81 b are placed in the orientation shown in FIG.9, so as to move air in the same direction, they may cooperate togenerate a draft across housing 12 and reduce airflow turbulence. Theuse of such fans can in certain applications eliminate the need for anoil cooler. The most advantageous arrangement of the fans will depend onhow apparatus 80 is located with respect to, e.g., a vehicle engine orthe like.

A fifth embodiment of this invention is shown in FIGS. 10-13, where pumpapparatus 90 has a housing 92. This embodiment is similar in many waysto the previous embodiments and in particular the embodiment shown inFIGS. 5 and 7 in terms of the arrangements of those items usingidentical numerals. The key difference in this embodiment is the use ofa single charge pump 98 driven by input shaft 94 rather than a pair ofcharge pumps driven by pump shafts 93 a and 93 b. Charge pump 98 ismounted in a housing 99 secured to cover 95.

As will be understood, a described arrangement requires porting to beformed in both cover 95 and housing 92 to permit charge oil flow to pumpcylinder blocks 31 a and 31 b. It would also be understood that suchporting could be formed externally, e.g., through hoses and therequisite fittings connecting charge pump 98 to end caps 96 a and 96 b.Input shaft 94 extends through cover 95 to drive charge pump 98. Theinput shaft may be further supported by bearing 77. An additionalbearing 97 may also be provided.

As shown most clearly in FIGS. 10 and 11, housing 92 and cover 95include a port 102 having a first leg 102 a extending into the left sideof housing 92 and into end cap 96 a, and a second leg 102 b extendingopposite thereto and through the right side of housing 92 and intosecond end cap 96 b. Charge inlet 104 is formed in cover 95 and connectscharge pump 98 to reservoir 68, as shown in the schematic shown in FIG.13. In the exemplary embodiment illustrated in FIGS. 10 and 11, bearing97 also serves to divide charge inlet 104 from port 102. End caps 96 aand 96 b, which are secured to housing 92 by screws 22 or otherfastening means, may be generally identical and thus only one will bedescribed.

End cap 96 a has a pair of system ports 105, each of which has acorresponding poppet valve 106 connecting the kidneys 107 to the systemports 105. A screw type bypass 108 can be used with a bypass port 109connecting the two sides of the hydraulic circuit to enable the user toplace the unit into bypass. The key distinction from the priorembodiments is the use of single charge port 103, which may be drilledinto end cap 96 a, and which connects to port 102 a to provide chargefluid from charge pump 98 to the hydraulic circuit of pump 11 a.

As can be seen most clearly in FIG. 12, a mounting flange 110 can beformed on housing 92 to provide a means for securing the pump apparatusto a vehicle or the like.

One of the benefits of this invention is that the design affordsflexibility to the user for different possible applications. Forexample, in FIGS. 1-3, trunnion arms 21 a and 21 b are shown extendingout of housing 12 on the same side as and thus parallel to input shaft14. It will be understood that trunnion arms 21 a and 21 b could bemounted on any side of housing 12, possibly requiring a correspondingchange in the orientation of swash plates 32 a and 32 b, respectively,and also possibly requiring a change in the orientation of end caps 16 aand 16 b, respectively. Trunnion arms 21 a and 21 b need not be on thesame side of housing 12. By way of example, if trunnion arm 21 a isrotated 180° from the orientation shown, housing 12 would need to bemodified, but the orientation of end cap 16 a would not need to bechanged. If, however, trunnion arm 21 a was rotated 90° from theorientation shown, end cap 16 a would also need to be similarly rotated,along with the proper housing modifications. These changes are depictedin FIGS. 15 and 16.

Specifically, a view of such an embodiment is shown in FIG. 15, wherepump apparatus 210 includes a slightly modified housing 212, wheretrunnion arms 21 a and 21 b are mounted on the same side of housing 212,but at a 90 degree angle from input shaft 14, so that trunnion arms 21 aand 21 b are perpendicular to both the two pump shafts 27 and 28 andinput shaft 14. FIG. 16 shows a slightly modified embodiment pumpapparatus 310, where trunnion arms 21 a and 21 b are mounted on oppositesides of housing 312. These changes are helpful to ensure that the unitcan be installed in a wide variety of applications. For example,different vehicle applications use different linkages, and the abilityto modify the pump housing in such manners affords the user maximumflexibility. It will also be understood that other types of swash plates32 a and 32 b, such as a trunnion mounted swash plate, could also beused.

Another area where this invention provides increased flexibility is inthe possible locations of the system ports. For example, in theembodiment depicted in FIG. 12, system ports 105 are located on the sideof end cap 96 a adjacent to mounting flange 110. In these embodiments,system ports 105 are parallel to the longitudinal axis of input shaft94. This is in contrast to, e.g., the embodiments shown in FIGS. 1 and9, where system ports 41 a, 41 b, 42 a and 42 b are formed in end caps16 a and 16 b, respectively, so as to be perpendicular to input shaft14. These different embodiments again increase the flexibility affordedto the user of this design, so that it may be used in a wide variety ofvehicles or other applications.

FIG. 14 shows an alternative embodiment similar to that shown in FIG.10, except that charge pump 112 is mounted on the inside of cover 111,and thus inside the fluid sump formed inside housing 92. Cover 113 isformed to mount not only charge pump 112 but also bearing 77 for inputshaft 114. Porting similar to that shown in FIG. 11 will be formed incover 111 to connect to ports 102 a and 102 b.

The tandem pump arrangements discussed above could be used in a modulefor installation in a vehicle such as a tractor, riding lawn mower orthe like. Such uses are exemplary, as other uses of the pump and motormodules disclosed herein will be obvious to one of skill in the art. Themodule may be a pump apparatus and a pair of wheel motors, or a pumpapparatus and an engine, or a pump apparatus with both the wheel motorsand the engine, depending on the application. Various embodiments of themodules in accordance with the present invention are depicted in thedrawings attached hereto as FIGS. 17 to 60. These embodiments arediscussed in detail below; the details of the pump apparatus used in thevarious modules are not discussed with respect to the figures. Manyelements of the vehicle and modules depicted in the differentembodiments discussed below are identical or substantially identical topreviously described elements and in such cases are given identicalreference numerals.

It will be understood by those of skill in the art that variousembodiments of hydraulic pumps, such as are described herein withrespect to FIGS. 1-16, can be used in connection with these modules.

FIGS. 17 through 24 show a first embodiment of such a module 115 inaccordance with the present invention. Vehicle 120 comprises a frame125, control mechanism 123, mower deck 127, deck drive system 117 andprime mover 121. Other known elements of such exemplary vehicles are notcritical to this invention and will not be described herein. One rearwheel 129 and other elements are removed from FIG. 17 for clarity. FIG.25 is a partial schematic view of an arrangement of a dual pump modulein accordance with an embodiment of this invention for use in a vehicle.

As shown in FIG. 18, drive module 115 is secured to vehicle frame 125 ina manner to be described below. As shown in FIGS. 19 to 24, drive module115 comprises a prime mover or engine 121, a mounting platform 136, apump mounting bracket 131, a pump apparatus 150, a pair of wheel motors140, a pair of stabilizing brackets 135, a motor mounting bracket 137and additional elements, some of which will be described in more detail.Each wheel motor 140 has a drive axle 128 extending therefrom to driveits corresponding wheel 129. The details of wheel motors 140 are notcritical to this invention and will not be described herein. A knownmotor design is shown in commonly owned U.S. Pat. No. 6,811,510, theterms of which are incorporated herein by reference. Other motor designscould be used with the modules of the present invention depending on theapplication. The disclosure herein assumes that both wheel motors areidentical, as this is preferred due to issues such as cost and ease ofassembly. It will be understood, however, that such identity is notrequired within the scope of this invention.

In the following discussions, reference may be made to drive modules andhydraulic modules; for example, drive module 115 and hydraulic module130. A drive module is generally an assembly that may include ahydraulic module, wheel motors, prime mover or engine, and all brackets,fasteners, lines and other elements required to accomplish the drivefunction for a vehicle. A hydraulic module generally has a pumpapparatus, motors or wheel motors, and all other elements required toform a hydraulic subassembly suitable for mounting into a vehicle.

As seen most clearly in FIGS. 18 and 20, each motor 140 is connected toa corresponding end cap 116 a or 116 b of pump apparatus 150 by means ofa pair of fluid passages 132 a, 132 b to provide high and low pressureflow between the pump apparatus 150 and motors 140. As shown mostclearly in the schematic view of FIG. 25, additional porting or tubes133 a are used to provide an inlet flow between reservoir 168 and pumpapparatus 150, through filters 165. Tubes 133 b provide a return flowfrom pump apparatus 150 to reservoir 168.

The embodiment depicted in these figures is of the direct drive type,where coupler 134 connects engine output 183 to pump input shaft 154.Output pulley 158 is mounted on the opposite side of pump shaft 154 andis used to engage and drive deck drive system 117 and mower deck 127. Anelectric clutch 160 may optionally be used to control this engagement.

A series of brackets are used to connect the various elements of module115. In the embodiment depicted in FIGS. 17 to 24, these bracketsinclude mounting platform 136, pump mounting bracket 131, stabilizingbrackets 135, mounting plates 126, motor mounting bracket 137, andcrossbar stabilizer 142. Stabilizing bracket 135 is shown in more detailin FIG. 23, while motor mounting bracket 137 is shown in more detail inFIG. 24. The names given these various brackets are for convenience andshould not be read as limiting. As will be understood, these bracketsare secured together by fasteners such as bolts 143, 144, 145 and 146;other fastening means could also be used. The number, size and locationof the fastening means will be known to those of skill in the art andwill depend on the application parameters.

In certain situations, the module may require additional stabilizingbeyond that provided by the various bracket members. A crossbarstabilizer 142 may be used in such instances, and its opposite endsextend through openings in various brackets and motors 140 that wouldotherwise be used for fasteners. In FIGS. 18 to 20, for example,stabilizer bar 142 is positioned by nuts 147 between stabilizingbrackets 135, and then extends through each bracket 153, through motormounting bracket 137 and then through motor 140, with another nut 147 tocomplete the attachment of stabilizer bar 142 to drive module 115.

Engine 121 is positioned on a mounting platform 136 that comprises agenerally flat area to which engine 121 is secured by means of mountingfasteners 144. A pair of flanges 136 a extending downwardly from eitherside, which are secured to mounting plates 126 on vehicle 120 framerails 125 by means of mounting bolts 143. Mounting plate 126 may beformed as a part of vehicle frame 125 or may be attached to vehicleframe 125 by fasteners or other methods, such as welding.

Stabilizing bracket 135 is shown separately in FIG. 23 and from a topview as a part of hydraulic module 130 in FIG. 21. It comprises a firstportion 135 a for support of one of the hydraulic motors 140 andincludes an opening 135 d to receive motor 140, a second portion 135 bfor attachment to one of the end caps 116 of pump assembly 150 andincludes opening 135 f to receive charge pump cover 118, and aconnecting portion 135 c joined to both sections 135 a and 135 b at agenerally perpendicular angle. Second portion 135 b includes an extendedtab having slot 135 g formed therein, to permit control arms 124 of pumpapparatus 150 to extend therethrough. Portion 135 b of stabilizingbracket 135 may be attached to pump apparatus 150 in a variety oflocations. In the embodiment shown in FIG. 21, stabilizing bracket 135is attached to pump module 150 by fasteners 122, which also serve toattach end cap 116 to pump apparatus 150. Openings 135 e are formed instabilizing bracket 135 to allow fasteners 122 to pass therethrough.

Motor mounting bracket 137 is shown separately in FIG. 24 and comprisesan opening 137 a corresponding to opening 135 d to receive motor 140.Motor mounting bracket 137 is secured to motor 140 and stabilizingbracket portion 135 a by the insertion of fasteners 141 through motormounting bracket openings 137 b and corresponding stabilizing bracketopenings 135 h.

Pump mounting bracket 131 is secured to the underside of mountingplatform 136. The extended tab portion of stabilizing bracket 135 isattached to pump mounting bracket 131 by fasteners 145 that extendthrough openings 135 j formed in stabilizing bracket 135 and similaropenings formed in pump mounting bracket 131.

Also shown in this embodiment is a clutch controlled power takeoff. Pumpapparatus is similar to pump apparatus 50 shown in FIG. 5 in that inputshaft 154 extends through pump apparatus 150. Adjacent to gear cavitycover 153 is a pulley 158. Shaft 154 extends through pulley 158 intoclutch 160, which is shown as an electric clutch. Clutch 160 uses ananti-rotation pin 161 to keep clutch 160 from spinning. Pin 161 may beattached to a bracket 162. Bracket 162 may be attached to pump apparatus150 by fasteners 163, which also attaches gear cavity cover to housing152 of pump apparatus 150. Clutch 160 may then be selectively engaged bya vehicle operator to connect shaft 154 to pulley 158, which may thendrive a feature such as mower deck 127.

Hydraulic module 130 permits a manufacturer to assemble various elementsof pumps and motors, including those shown in FIG. 25, and either attacha prime mover such as prime mover 121 to form drive assembly or module115, or transport hydraulic module 130 to another location for furtherassembly. Drive module 115 and hydraulic module 130 provide clearance148 to permit sliding either drive module 115 or hydraulic module 130from the rear of vehicle 120 toward the front of a vehicle 120 overframe rails 125 and any associated elements, such as mounting plate 126.Thus, drive module 115 and hydraulic module 130 provide an assembly thatcan easily be manufactured and transported to a vehicle manufacturer forassembly into a vehicle, reducing vehicle assembly time and costs.

FIGS. 26 to 30 depict another embodiment of this invention, and inparticular a vehicle 220 including a drive module 215. As seen mostclearly in FIG. 28, a bell housing 231 is integrally formed as part ofhousing 252 of pump apparatus 250. Bell housing 231 is then secured tothe underside of mounting platform 236 by means of fasteners 144 orother fastening means. Stabilizing brackets 235 are used to connectwheel motors 140 with end caps 116 a and 116 b of pump assembly 250.Crossbar stabilizer 142 is again used to provide additional support andstability. Control arms 224 extend from the top side of dual pumpapparatus 250. This embodiment permits a simplified support of pumpapparatus 250 as compared to the embodiment shown in FIGS. 17 to 24. Useof bell housing 231 reduces the complexity of drive module 215 ascompared to drive module 115, providing additional clearance for vehicleelements that may need to be connected to drive module 215 or may needto pass from one side of module 215 to the other side of module 215.Note that bell housing 231 may be attached directly to prime mover 121through an opening formed in mounting platform 236 (not shown), or itmay be positioned adjacent to the lower surface of mounting platform 236and attached to mounting platform 236 or to prime mover 121 by fasteners(not shown) that penetrate mounting platform 236 through clearance holes(not shown).

A further embodiment of a vehicle 320 having a pump and engine module315 is depicted in FIGS. 31 to 34. Stabilizing brackets 335 are securedto vehicle 320 frame 325 by attachment to mounting plates 326 withfasteners 346. Mounting platform 336 is also attached to mounting plate326 by fasteners 343. Stabilizing brackets 335 may also be secured topump mounting bracket 131 by fasteners 145. As previously described,pump mounting bracket 131 may be attached to prime mover 121 byfasteners 144. As in a previously described embodiment, mounting plate326 is secured to frame 325 by fasteners or a technique such as welding.Stabilizing bracket 335 may be similar in construction to stabilizingbracket 135 described above. This embodiment demonstrates that wheelmotors 140 may be offset lower than pump apparatus 350 with respect tothe ground; minor modifications such as to the shape of passages 332 aand 332 b can be made to accommodate such an offset. Further differencesinclude the location of pulley 158 below electric clutch 160. Inaddition, four stabilizer bars 142 are used; two are shown in the frontview of FIGS. 32 and 34; two more can be located in the correspondingrear positions as shown in FIG. 33. Flanges 336 b are formed on the foreand aft sides of platform 336 to provide stiffness to support the weightof engine 121 and resist excessive torquing of vehicle frame.

Another embodiment is shown in FIGS. 35 to 37, where hydraulic module430 cannot accommodate a pre-mounted engine and hydraulic module 430 isinstalled from under chassis 425 and mounting plate 426. Thisconfiguration moves engine 121 further to the rear of axles 128 than thepreviously described embodiments. A more substantial mounting plate 426is used in this configuration and the wheel motor portion of stabilizingbracket 435 is secured to plate 426 with fasteners 446 and fasteners 141only mount motor 140 to stabilizing bracket 435. Mounting platform 336is secured to plate 426 by fasteners 443. One crossbar stabilizer 442 isshown. Fluid passages 432 a and 432 b are used similar to the priorembodiments.

A further embodiment of a vehicle 520 having a drive module 515 mountedthereon is shown in FIGS. 38 to 40. The primary difference between thisembodiment and those previously discussed is in the shape of the variousbrackets and the orientation of the hydraulic lines toward the rear ofvehicle 520, to provide better protection and accessibility.

Pump apparatus 550 is attached to stabilizing brackets 535 as are motors140. This assembly is mounted to vehicle 520 by inserting module 515into cutouts shown in mounting plates 526 from the rear of vehicle 520.Stabilizing brackets 535 may then be attached to mounting plates 526 bymeans of fasteners 546 and mounting platform 336 is attached to mountingplates 526 by means of fasteners 543.

A single crossbar stabilizer 542 is provided near the front of module515 connecting the two mounting plates 526. Additional stabilizer(s)could be used if required for additional stability and frame stiffness.Note that stabilizer 542 is not part of drive module 515.

A further embodiment of another vehicle 620 incorporating a drive module615 is shown in FIGS. 41 and 42, where output axles 128 are in the samevertical plane as the dual pump shafts (not shown) of pump apparatus650.

Two stabilizer rods 642 are shown as being in the same horizontal planeas output axles 128. Similar to the previous embodiments, mountingplatform 636 is mounted on vehicle frame members 625; mounting plates626 are secured to frame members 625 by weldments. Mounting platform 636is attached to mounting plates 626 by fasteners 643. Motors 140 arelocated in mounting platform 636. This embodiment includes an integralbell housing 231 formed as a part of the housing of pump apparatus 650.

FIG. 43 shows a drive module 685 embodiment similar to that shown inFIGS. 41 and 42, using a pump apparatus 550 mounting similar to thatshown in various figures; for example, see FIGS. 18, 20, 32, and 39.Note that attachment plate 635 is a simpler part than that shown inprevious embodiments.

A further embodiment of this invention is depicted in FIGS. 44 and 45,where vehicle 720 comprises drive module 715 mounted on the inside offrame rails 625 as shown most clearly in FIG. 45. Mounting platform 636is mounted to flange 626 extending from frame rails 625 with bolts 643.This embodiment increases the ease of assembly, as module 715 may beraised, or frame 625 lowered, into position during installation.

In this embodiment, the input and output shafts and axles 128 are all onthe same vertical plane, resulting in a lesser material requirement fora vertical shaft engine application. Two stabilizer/alignment rods 642are shown in the same horizontal plane as the axles 128.

FIG. 46 is a rear elevational view of a further embodiment similar tothat shown in FIGS. 44 and 45, incorporating a crossbeam approach havingdrive module 785 in a structural configuration. Drive module 785 ismounted to the inside of vehicle frame 625. U-brackets 735 between pumpapparatus 550 and motors 140 can be mounted in various orientations.This embodiment depicts a direct drive between engine 121 and dual pump550.

FIG. 47 is a rear elevational view of drive module 815, incorporatingrectangular or square tubes 835 instead of the U-brackets usedpreviously. The use of the crossbeam approach plus bell housing 231yields a more substantial structure and the input shaft is hidden andseals are protected. Tubes 835 and stiffening plates 837 are shownbetween pump apparatus 650 and motors 140. Mounting platform 636 andplates 837 may be attached to mounting plate 626 by fasteners 843.Square or rectangular tubes 835 can be rotated 90 degrees so that thefour walls of tubes 835 are in a vertical orientation as opposed to thehorizontal orientation depicted. Such an orientation is shown in FIG. 48as drive module 885. Hose mounting clamps 839 are attached to thevertical walls of structural tubes 835.

Yet another embodiment is depicted in FIGS. 49 to 52, incorporatingcastings 895 secured between dual pump apparatus 650 and motors 140.Drive module 891 is mounted to the inside of vehicle frame members 625.One casting 895 is shown sectioned vertically on the axle 128 centerlinefor clarity. As in other embodiments, the use of the crossbeam approachplus bell housing 231 yields a more substantial structure and the inputshaft is hidden and seals are protected. A preferred structure ofcasting 895 is shown in FIGS. 50 to 52, where flange 895 a includes aplurality of fastener openings 895 c to secure casting 895 to end caps116 a, 116 b through fasteners 893, and mounting surface 895 b includesa plurality of fastener openings 895 d to secure motors 140 to castings895 with fasteners 897, which may also secure motors 140 to a structuralelement such as mounting platform 636.

An additional embodiment is shown in FIGS. 53 to 58. Drive module 915 isinstalled in vehicle 919 with a straight frame 925. Mower deck 927 isshown in the lowered position, and most of the near side frame rail 925is shown cut away to show module 915 more clearly.

Pump apparatus 950 is attached by way of adapter 955 to prime mover 921.Fasteners 956, 957 and 958 are used to mate bell housing 951 to pumpapparatus 950 and to adapter 955, and to mate adapter 955 to prime mover921. Pump apparatus 950 also comprises a hydraulic clutch and brake 959.Clutch 959 drives power take off shaft 960, which then drives shaft 917and then mower deck 927.

Motors 140 are mounted by way of brackets 939 to mounting platform 937that also supports prime mover 921. Bracket 939 also comprises an angle942 to interface with frame 925. Fasteners 943 may optionally securebracket 939 to frame 925. A spacer 945 may be used to prevent collapseof frame 925 as each fastener 943 is tightened.

To aid in securing pump apparatus 950, support assembly 970 is locatedon hydraulic clutch 959. An optional vibration isolator 971 may also beassociated with support assembly 970. Trunnions 924 a and 924 b may faceupward for ease of attachment to vehicle linkage 923.

Coupler 934 may be used to mate pump apparatus 950 input shaft 954 to aprime mover 921 output shaft. The advantage of this configuration isthat it permits a wider vehicle wheel base compared to other designs andalso permits a lower center of gravity for vehicle 919 as compared toother designs.

Yet another embodiment is depicted in FIGS. 59 and 60, which is verysimilar to the previous embodiment shown in FIGS. 53 to 58, but there isan offset bend in frame 926. The offset bend in frame 926 allows drivemodule 985 to keep many of the features of the embodiment shown in FIGS.53 to 58 while permitting a narrower stance of wheels 930 as compared towheels 929.

As best seen in FIG. 60, wheel motor brackets 940 are configured toposition wheel motors 140 below and partially directly under frame 926.Bracket 940 may be welded or attached to mounting platform 938, which issupported by structural tubes 941. As in the previous embodiment,fasteners 943 may aid in attaching mounting platform 938 to frame rail926 at angle 942 formed as part of mounting platform 938. Spacer 945helps prevent the collapse of frame member 926 during tightening offastener 943.

In each of these embodiments, the dual pump is depicted to be similar tothat disclosed in FIGS. 1-16 above. However, it will be understood thatother dual pump arrangements can be used in connection with the modulesdisclosed herein in keeping with the spirit of this invention.

It is to be understood that the above description of the inventionshould not be used to limit the invention, as other embodiments will beobvious to one skilled in the art. This invention should be read aslimited by the scope of its claims only.

1. A hydraulic apparatus for use in connection with a vehicle,comprising: a pump apparatus, comprising: a housing element having afirst pump chamber, a second pump chamber, and a gear chamber; a firstpump driven by a first pump shaft disposed in the first pump chamber; asecond pump driven by a second pump shaft disposed in the second pumpchamber, wherein the second pump shaft is generally coaxial with thefirst pump shaft; and an input shaft having a first gear mounted thereonand drivingly connected to the first pump shaft and the second pumpshaft; a pair of hydraulic motors, each hydraulic motor beinghydraulically connected to one of the pumps; and a bracket assembly formounting the pump apparatus and the pair of hydraulic motors to thevehicle, the bracket assembly comprising: a pump bracket attached to thehousing element of the pump apparatus; a first bracket member attachedto one of the pair of hydraulic motors; a second bracket member attachedto the other of the pair of hydraulic motors; a third bracket memberextending from the first bracket member to the second bracket member,wherein the first and second bracket members and the pump bracket aresecured to the third bracket member and wherein the third bracket membercomprises a single piece forming a generally flat mounting surface foran engine; and a plurality of attachment points for securing the bracketassembly to the vehicle.
 2. The hydraulic apparatus of claim 1, whereinthe pump bracket comprises a bell housing that generally surrounds theinput shaft.
 3. The hydraulic apparatus of claim 2, wherein the bellhousing is integrally formed with the housing element.
 4. The hydraulicapparatus of claim 1, wherein each motor comprises a motor shaft, andthe bracket assembly positions the pair of hydraulic motors so that themotor shafts are generally collinear with each other and offset from theaxis of the first pump shaft and the second pump shaft.
 5. The hydraulicapparatus of claim 1, wherein each motor comprises a motor shaft, andthe bracket assembly positions the pump apparatus and the hydraulicmotors so that the motor shafts and the pump shafts are generallycollinear.
 6. The hydraulic apparatus of claim 1, wherein the pumpbracket comprises a first piece secured to one end of the housingelement of the pump apparatus and a second piece secured to a second endof the housing element of the pump apparatus.
 7. A hydraulic apparatusfor use in connection with a vehicle, comprising: a pump apparatus,comprising: a housing element having a first pump chamber, a second pumpchamber, and a gear chamber; a first pump driven by a first pump shaftdisposed in the first pump chamber; a second pump driven by a secondpump shaft disposed in the second pump chamber, wherein the second pumpshaft is generally coaxial with the first pump shaft; and an input shafthaving a first gear mounted thereon and drivingly connected to the firstpump shaft and the second pump shaft; a pair of hydraulic motors, eachhydraulic motor being hydraulically connected to one of the pumps, and apair of motor shafts, wherein each motor engages and drives one of themotor shafts; and a bracket assembly for mounting the pump apparatus andthe pair of hydraulic motors to the vehicle, the bracket assemblycomprising: a pump bracket attached to the housing element of the pumpapparatus; a first bracket member attached to one of the pair ofhydraulic motors; a second bracket member attached to the other of thepair of hydraulic motors; a third bracket member extending from thefirst bracket member to the second bracket member, wherein the first andsecond bracket members and the pump bracket are secured to the thirdbracket member; and a plurality of attachment points for securing thebracket assembly to the vehicle; wherein the bracket assembly positionsthe pump apparatus and the hydraulic motors so that the motor shafts andthe pump shafts are generally collinear.
 8. The hydraulic apparatus ofclaim 7, wherein the pump bracket comprises a bell housing thatgenerally surrounds the input shaft.
 9. The hydraulic apparatus of claim8, wherein the bell housing is integrally formed with the housingelement.
 10. The hydraulic apparatus of claim 7, wherein the pumpbracket comprises a first piece secured to one end of the housingelement of the pump apparatus and a second piece secured to a second endof the housing element of the pump apparatus.
 11. A hydraulic apparatusfor use in connection with a vehicle, comprising: a pump apparatus,comprising: a housing element having a first pump chamber, a second pumpchamber, and a gear chamber; a first pump driven by a first pump shaftdisposed in the first pump chamber; a second pump driven by a secondpump shaft disposed in the second pump chamber, wherein the second pumpshaft is generally coaxial with the first pump shaft; and an input shafthaving a first gear mounted thereon and drivingly connected to the firstpump shaft and the second pump shaft; a pair of hydraulic motors, eachhydraulic motor being hydraulically connected to one of the pumps; and abracket assembly for mounting the pump apparatus and the pair ofhydraulic motors to the vehicle, the bracket assembly comprising: a pumpbracket attached to the housing element of the pump apparatus andcomprising a first piece secured to one end of the housing element ofthe pump apparatus and a second piece secured to a second end of thehousing element of the pump apparatus; a first bracket member attachedto one of the pair of hydraulic motors; a second bracket member attachedto the other of the pair of hydraulic motors; a third bracket memberextending from the first bracket member to the second bracket member,wherein the first and second bracket members and the pump bracket aresecured to the third bracket member; and a plurality of attachmentpoints for securing the bracket assembly to the vehicle.
 12. Thehydraulic apparatus of claim 11, wherein the pump bracket comprises abell housing that generally surrounds the input shaft.
 13. The hydraulicapparatus of claim 12, wherein the bell housing is integrally formedwith the housing element.
 14. The hydraulic apparatus of claim 11,wherein each motor comprises a motor shaft, and the bracket assemblypositions the pair of hydraulic motors so that the motor shafts aregenerally collinear with each other and offset from the axis of thefirst pump shaft and the second pump shaft.